#include <bits/stdc++.h>
#define REP2(i,x,n) for(int i=x; i<(n); i++)
using namespace std;
int main()
{
	cin.tie(0);
	ios::sync_with_stdio(false);

	vector<int> M{ 0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };
	int count{};
	REP2( i, 1, 12 ){
		REP2( j, 1, M[i] + 1 )
		{
			if( i == ( j % 10 ) + ( j / 10 ) )
			{
				count++;
			}
		}
	}
	cout << count << endl;
	return 0;
}